Delay Analysis for Different Resource Allocation Schemes in Wireless Networks

In this paper, we study the delay performance of wireless network considering different resource allocation schemes with single-hop traffic. Existing works studying the delay performance only consider a given resource allocation scheme, either multi-channel system (sharing bandwidth) or time slotted system (sharing time). The fundamental question ignored is which type of resource allocation scheme produces better delay performance with different network configurations, such as number of commodities, traffic statistics. We investigate the impact of different resource allocation schemes on the delay performance. A new arrival mode is designed for the time slotted system to reduce the average delay. We also construct the delay lower bound taking the perfect scheduling policy and queue management into account. We get four important conclusions from the numerical results: 1) the new arrival mode produces better delay performance than the regular mode, and it is immune to the change of time slot length. 2) time slotted system has better delay performance than multi-channel system, and almost achieves the lower bound, 3) the scalability of the multi-channel system is not good, since the delay will be very large with a large number of commodity flows. While time slotted system is scalable with a converging delay value with the infinite number of commodities. 4) both the multi-channel system and time slotted system are sensitive to the difference between arrival rate and service rate, which means that the delay is large when arrival rate is close to service rate.